1. Field of the Invention
The invention relates to a temperature sensitive device, and more particularly to a temperature sensitive device capable of generating an effect comparable to two-point calibration through a single one-point calibration.
2. Description of the Related Art
FIG. 1 is a diagram showing the relationships of three output signals that are respectively from three temperature sensitive devices (not shown) manufactured with different manufacturing process drifts and calibrated through the conventional one-point calibration. The output signals of the temperature sensitive devices substantially have the same magnitude only at a temperature T1 corresponding to a calibration point A. Differences among the output signals from the temperature sensitive devices that use one-point calibration thus will become bigger as the sensed temperature approaches a lowest temperature T1−ΔT or a highest temperature T1+ΔT of a sensing range.
Referring to FIG. 2, in order to alleviate the above drawback of one-point calibration, a calibration point B that is different from the calibration point A must be introduced, such that the output signals of the temperature sensitive devices will have approximate magnitudes when the temperature that is being sensed ranges between T1 and T2, wherein T1 is the temperature corresponding to the calibration point A and T2 is the temperature corresponding to the calibration point B, and a sensing range is defined between T1 and T2.
Therefore, it is evident that the differences among the output signals from the temperature sensitive devices adopting conventional one-point calibration within sensing ranges thereof are larger than the differences among the output signals from the temperature sensitive devices adopting two-point calibration within sensing ranges thereof.